One of the chief architects of Obamacare, Sen. Jay Rockefeller, has launched a scathing attack on the program, arguing that it is too complex and that program managers could imperil the program’s future.

“I believe the Affordable Care Act is probably the most complex piece of legislation ever passed by the United States Congress,” the retiring West Virginia Democrat said on Tuesday, according to the Washington Examiner. “Tax reform obviously has been huge too, but up to this point it is just beyond comprehension,” he added.

Rockefeller also criticized program managers, saying they were not moving quickly enough to build the system. He said that Obamacare is “so complicated and if it isn’t done right the first time, it will just simply get worse,” the Examiner reported.

His candid remarks were made during the Senate Finance Committee confirmation hearing for Marilyn Tavenner to become the next administrator of the Centers for Medicare & Medicaid Services.

One of the chief architects of Obamacare, Sen. Jay Rockefeller, has launched a scathing attack on the program, arguing that it is too complex and that program managers could imperil the program's future.